Reduction-magnetic Separation

Experimental Study on Reduction-Magnetic Separation Process of Low-grade Nickel Laterite Ore... 

Key words low-grade, laterite, reduction-magnetic separation, nickel... 

In order to find out the phase composition of fine laterite ore reduced with reduction temperature of 1375°C, the atomic ratio of C/O of 1.2, and the percentage of CaO of 12%, the samples were examined by X-Ray fluorescence(XRF), X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer (EDS). The chemical compositions of the fine ore by reduction-magnetic separation was shown in Table 3.1, the XRD pattern of fine ore by reduction-magnetic separation was seen in Fig.3.5, and the SEM pattern of fine ore by reduction-magnetic separation was shown in Fig.3.6 and the chemical compositions of observed district in SEM pattern was shown in Table 3.2. 

Key words High Iron Content Manganese Ore, Reduction Magnetic Separation. 

SL/RN Process. In the SL/RN process (Fig. 4), sized iron ore, coal, and dolomite are fed to the rotary kiln wherein the coal is gasified and the iron ore is reduced. The endothermic heat of reduction and the sensible energy that is required to heat the reactants is provided by combustion of volatiles and carbon monoxide leaving the bed with air introduced into the free space above the bed. The temperature profile in the kiln is controlled by radial air ports in the preheat zone and axial air ports in the reduction zone. Part of the coal is injected through the centerline of the kiln at the discharge end. The hot reduced iron and char is discharged into an indirect rotary dmm cooler. The cooled product is screened and magnetically separated to remove char and ash. 

Kotani, M., Koike, T., Yamaguchi, K. and Mizuno, N. (2006) Ruthenium hydroxide on magnetite as a magnetically separable heterogeneous catalyst for liquid-phase oxidation and reduction. Green Chemistry, 8 (8), 735-741. 

Production of cobalt in general is based on various physical and chemical processes that include magnetic separation (for arsenic sufide ores), sulfatiz-ing roasting (for sulfide ores), ammoniacal leaching, catalytic reduction, and electrolysis. 

Size reduction followed by physical processes such as magnetic separation or flotation... 

Magnetic Separation. The future utility of pyrolysis as a process depends upon the successful use of the char. From the discussion on sulphur transfer, it is evident that as the result of pyrolysis some sulphur which is difficult to remove physically (well disseminated pyrite) is transformed to sulphur that is impossible to remove physically (organic sulphur). In addition it has been shown that this newly formed, organic sulphur is present in a very stable form. This would seem to be counter productive to any scheme which must include sulphur reduction as a primary goal. However, by carefully controlling the pyrolysis reaction conditions it should be possible to produce chars which are amenable to sulphur reduction by magnetic separation. 

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